Prevalence of HIV Among Injection Drug Users in Australia: "The prevalence of HIV among people who inject drugs in Australia has remained low at 2.1% or less since 1995. The prevalence of HIV in 2011 was 1.2% (Figure 46). HCV prevalence among this group was much higher at 61% to 62% from 2005 to 2008, however this figure was lower at 53% 2011 (Figure 46) (Iversen and Maher, 2012)."
"Cigarette smoking has been shown in other studies to act as a 'gateway' to cannabis use and further risk taking behaviours. This study aims to establish the prevalence of cigarette smoking and cannabis use in Irish teenagers, to quantify the strength and significance of the association of cigarette smoking and cannabis use and other high risk behaviours and to examine whether the above associations are independent of social networking (O'Cathail, et al. 2011).
"26.4% of Irish adults aged 15 years or older report using an illegal drug in their lifetime, 7.5% in the past 12 months and 4.0% in the past month.
" Lifetime usage of cannabis (24.0%) is considerably higher than any other form of drug. The second most commonly used drug is ecstasy (7.8%) with lifetime usage of cocaine (including crack) and cocaine powder at 6.6% and 6.4% respectively.
"The findings on drug use are based partly on positive findings from urine tests and partly on reported use during the last 30 days. The levels are overall quite similar to 2012. A proportion of 10 per cent reported having used an illegal morphine substance during the past month, 33 per cent cannabis, 16 per cent stimulants and as many as 42 per cent benzodiazepines. This figure includes both prescribed and non-prescribed benzodiazepines. Twenty-five per cent of all patients report having been prescribed the drug by a doctor. In other words, the others must have used illegal sources.
"The estimated number of injecting drug users in Norway was also reported prior to the revision, using the mortality multiplier method. This method divides the number of drug-related deaths by the likelihood of dying of a drug-related diagnosis in the population of injectors in the 15–64 age group. First, an estimate of the number of recreational users was subtracted from the nominator because they are less likely to have injected the substance that caused the death.
"In line with a number of other studies, the 2013 survey shows that cannabis is by far the most common illegal drug in Norway. As shown in Figure 2, the LTP rate for cannabis use among all adults was 23.3 per cent, while the LYP rate was 5.1 per cent. By comparison, the LTP rate was estimated to be 4.2 per cent for cocaine, 3.7 per cent for amphetamines, 2.3 per cent for ecstasy, 1.5 per cent for LSD, 1.1 per cent for GHB/GBL and 0.7 per cent for heroin for all adults (Figure 3). The LYP rate was estimated to be less than one per cent for cocaine, amphetamines and ecstasy.
"By combining the data from 2012 and 2013, we can obtain more precise estimates of prevalence levels for cannabis use and differences between subgroups. The estimated LTP [lifetime prevalence], LYP [last year prevalence] and LMP [last month prevalence] rates among all adults (aged 16–64) were 21.3 per cent, 4.3 per cent and 1.6 per cent, respectively. Among young adults (aged 16–34), the corresponding LTP, LYP and LMP estimates are 30.2 per cent, 10 per cent and 3.4 per cent.
Estimated Prevalence of Cannabis Dependence or Abuse in the US
" Marijuana is by far the most widely used illicit drug. Nearly half of all 12th graders (45%), nearly one third of 10th graders (31%), and over one in seven 8th graders (14%) reported some marijuana use in their lifetime. Among 12th graders, 37% reported some use in the past year, and 23% reported some use in the past month. Among 10th graders, the corresponding percentages were 26% and 16%, respectively, and among 8th grade students, 10% and 5.5%.
"Comparisons with the previous four sweeps of the SCJS [Scottish Crime and Justice Survey] help to put these findings in context and reveals that the percentage of adults reporting using one or more illicit drugs has been declining. Table 2.1 and Figure 2.1 show this decline in the number of adults reporting illicit drug use for all three time periods used in the survey between the SCJS 2008/09 and the SCJS 2014/1510. The decline was significant comparing drug use reported in the 2008/09 survey with that reported in 2014/15.